Conduit cleaning apparatus

ABSTRACT

A conduit cleaning apparatus of the type for driving rods flexibly connected in end-to-end relationship with a cleaning tool at one end into and out of a conduit. The assembly includes a rotatably mounted rod storage device having an opening for ingress and egress of the rods and a chain mounting pusher blocks for propelling the rod into a conduit. The upper and rod driving run of the chain is mounted coaxially with the opening in the storage means so that the driving run of the chain is easily accessible. Sprockets mounting the chain are spaced by elongated elements extending directly between the sprockets so that forces applied to the frame are either tensional or compressional and do not create substantial bending moments. A control for the drive includes a system wherein the force applied to the rods, while being driven into a conduit in compression, is less than that applied when the rods are removed from the conduit and in tension.

United States Patent Siegal 1451 Dec. 19,1972

[54] CONDUIT CLEANING APPARATUS [72] Inventor: Burton L. Siegal, Chicago, Ill. [73] Assignee: Conco Inc. I

[22] Filed: Sept. 9, 1970 [21] Appl. 196.; 70,774

Primary ExaminerEdward L. Roberts Attorney-Hofgren, Wegner, Allen, Stellman & Mc- Cord [s7]. 7 ABSTRACT Aconduit cleaning apparatus of the type for driving rods flexibly connected in end-to-end relationship with a cleaning tool at one end into and out of a conduit. The assembly includes a rotatably mounted rod storage device having an opening for ingress and egress of the rods and a chain mounting pusher blocks for propelling the-rod into a conduit. The upper and rod-driving run of the chain is mounted coaxia'lly with the opening in the storage means so that the driving run of the chain is easily accessible. Sprockets mounting the chain are spaced by elongated elements extending directly between the sprockets so that forces applied to the frame are either .tensional or compressional and do not create substantial bending moments.

A control for the drive includes a system wherein the force applied to the rods, while being driven into a conduit in compression, is less than that applied when the rods are removed from the conduit and in tension.

8 Claims, 4 Drawing Figures PATENTED HEB 19 I972 SHEET 2 OF 2 CONDUIT CLEANING APPARATUS BACKGROUND OF THE INVENTION Sewer cleaners of the type which propel flexible, steel sewer cleaning rods flexibly interconnected in end-to-end relationship through sewers or the like to clean the same have achieved considerable success in solving sewer maintenance problems of municipalities and the like. Most frequently, the same include a rotatable storage device for storing the rods with the storage device having an opening through which the rods may pass while being propelled into or out of the sewer or the like. While the rods are being propelled into a sewer, the storage device is rotated to thereby rotate the rods as they are advanced within the conduit so that a sewer cleaning tool at one end of the length of rod will be moved both axially and rotatably through the sewer to clean the same.

The rods are moved through the opening by a chain mounting pusher blocks which engage. the couplings between adjacent rods to drive the length of rods. Typically, the chain is trained about a pair of sprockets which are mounted for rotation about a horizontal axis above the axis of the opening from the storage means with the lower run of the chain and the pusher blocks thereon engaging the rods. The sprockets are mounted on shafts which in turn are rotatably mounted in bearings received within structural towers extendingupwardly from the frame of the machine. The drive for the sprockets quite typically is of the variable speed type so that the rate of advance or egress of the rods with regard to a conduit or sewer may be selectively varied.

The just-described prior art construction, while successful as noted above, has a number of drawbacks and disadvantages. For example, because the driving unit is mounted in such a way that the lower run of the chain drives the rods, when there is a jamup of the rods in the driving zone, it is extremely difficult to achieve access to the jamup and clear the same. In fact, it has been necessary to practically fully disassemble the driving unit including the structural towers mounting the sprockets, etc. to achieve access. Furthermore, because the shafts mounting the sprockets are mounted in towers, the towers must be extremely strong as must be the frame mounting the towers themselves as a substantial bending moment is applied when the device is in operation. Also, the relatively high location of the driving element raises the center of gravity of the entire machine and since such devices are quite typically mounted on truck beds or trailers, a considerable degree of unnecessary instability is introduced into the vehicle when the same is being moved from location to location. Finally, the very nature of the rods and the operation in which they are used is such that when the rods are being driven into a sewer and therefore compressionally loaded, they have a great tendency to bend and break if too great a driving force is applied to them. In other words, the rods should be driven into a conduit with a maximum force that is less than the maximum force permitted in removing the rods from a sewer. While the prior art has provided adjustable devices whereby the amount of force applied to the rods can be changed manually, if desired depending upon whether the rods are being introduced into or from a conduit, in practice, an operator of the device will not always change the adjustment upon changing the direction of travel of the rods so that either the rod introducing operation or the rod removing operation is inefficient and/or can lead to damage of the equipment.

SUMMARY OF THE INVENTION It is the principal object of the invention to provide a new and improved sewer cleaning apparatus of the type employing flexible rod elements which minimizes frame-strength requirements, improves unit stability when in transit, permits easy access to rod jams in the driving mechanism and which automatically adjusts loading of the rod-like elements depending upon whether they are being introduced into a sewer or removed therefrom.

The foregoing objects are achieved in the exemplary embodiment through a construction wherein the driving mechanism comprising a chain mounting pusher block is arranged with respect to an opening in a storage means for the rods so that the uppermost run of the chain constitutes the driving run thereof whereby easy access to rods jammed in the driving zone may be had. Furthermore, sprockets about which the chain is trained are mounted on shafts which are held in spaced apart relationship by a pair of elongated elements flanking the chain and extending directly between the shafts so that loading of the frame is principally tensional or compressional with substantially no bending moments thereby minimizing strength requirements of the frame. In the exemplary embodiment,the two elongated elements comprise downwardly extending flanges of an inverted channel with the base of the channel supporting and limiting downward movement of the driving run of the chain. Furthermore, the base of the channel may include a hardened portion which engages the chain for increased wear. The sprocket mounting shafts are in turn supported by bearings depending from the base of the channel and within the vertical dimension of the flanges mentioned above.

For driving purposes, the exemplary embodiment employs a hydraulic motor of the type wherein hydraulic fluid under pressure is introduced into one port to cause the motor to drive in one direction and into another port when the motor is to drive in the other direction. A pair of pressure limiting valves, one for each port, are interposed between the respective ports and a hydraulic pump and the valves are independently settable in advance of the operation so that the total driving force applied to the chain for the opposite direction of movement whereby significantly greater force is applied by the chain to the rods when removing the same from the sewer than when causing the same to enter a sewer.

Other objects and advantages of the invention will become apparent from the following specification taken in conjunction with the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a conduit cleaning apparatus embodying the invention;

FIG. 2 is a plan view of the rod driving mechanism employed in the invention;

FIG. 3 is a vertical section taken approximately along the line 3-3 of FIG. 2; and

FIG. 4 is a vertical section of the drive mechanism taken approximately along the line 4-4 of FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT An exemplary embodiment of the invention is illustrated in FIG. 1 and is seen to be mounted on the frame of a vehicle, generally designated 12, and having wheels 14. While the vehicle 12 is shown to be a twowheel trailer, the same could be a truck having a flat end-to-end relation by couplings 26 of well-known construction. One end of the length of rods 24 extends through a funnel-like opening 28 in the storage means 22 to a rod driving mechanism defining a driving zone, generally designated 30. The opening 28 is defined by a horn-like element 32 having one end joumalled in bearings 34 mounted on a cross member 36 secured between a pair of upright posts 37 secured to the vehicle frame 10. As a result'of theforegoing construction, the storage means 22 may be rotated to impart rotation to the length of rods 24 whether within or without the confines of the storage means 22.

To impart such rotation to the storage means, a driven element 38 in the form of a sprocket or a sheave is secured to one endof the storage means 22 and has a flexible driving element 40 (either a chain or a V-belt depending upon whether the driven element 38 constitutes a sprocket or a sheave) trained thereabout and extending to a driving element 42 mounted for rotation with a' driving shaft 44.

Turning now to FIG. 2, the shaft 44 is joumalled in bearings 46 and mounts, at one end, a sheave 48 which may be driven frictionally by a V-belt (not shown) which in turn is driven by an internal combustion engine 50. The opposite end of the shaft 44mounts a disc 52 forming part of a disc brake and which has a portion of its periphery interposed between a pair of brake elements 54 suitably mountedon the frame. One of the brake elements 54 is movable toward the disc 52 by means of the cam 56 which is operated by a link 58 connected to an arm 60 on a shaft 62 (FIG. 1). The shaft 62 is suitably joumalled on the frame and includes an operating handle 64 which may be pivoted to release the brake elements 54 or engage them with the disc 52.

The shaft 62 also mounts, for rotation therewith, an arm 66 having depending links 68 which support an idler sheave 70 about which the V-belt from the engine 50 to the sheave 48 is trained. Finally, there is provided a conventional over center spring mechanism,

generally designated 72, to bias the shaft 62 to any and the sheave 48 to cause rotation of the storage device 22. When the handle 64 is pivoted in the opposite direction, the movable brake element 54 will be moved into contact with the disc while the idler sheave 70 will permit the V-belt to loosen to simultaneously break the driving connection to the storage means 22 and halt rotation of the same through action of the brake. The biasing means 72 serves to bias the shaft 62 into either one of abrakin'g, non-driving position, and a driving, non-braking position through its over center action. 7

i In addition to the engine 50, the frame 10 mounts a storagebattery 74 which may be used in conjunction with an electric starter to start the engine 50, and a selfcontained hydrostatic pump and motor 76 of conventional construction. A flexible coupling 78 establishes a driving relation between the engine and the'pump and motor 76 and the latter includes a pair of ports connected to hydraulic fluid lines 80 and 82 shown in schematic form for. purposes to be seen. If desired, suitable pressure meters 84 may be interposed in each of the lines 80 and 82.

The swash plate controlrod of the pump and motor 76 is provided with a rotatable extension 86which is joumalled in a bearing 88 connected to a frame member and includes a horizontally extending arm 90 (FIGS. 1 and 2). One end of the arm 90 is connected through a link 92 to a control handle 94 which is pivotally connected to a frame member as at 96; The control handle 94 is manually operable to co'ntrolboth the direction and the rate of feed of the rods in a manner to be seen.

As best seen in FIG. 2, a right angle gear box 98 is connected to the pump and motor 76 and includes a rotary outputshaft 100 from which rotary motion is taken to ultimately propel the rods 24 within a conduit. Returning to FIG. 1 and the hydraulic lines 80 and 82 shown therein, the same terminate in respective valves 101 and 102 which are conventional manually adjustable pressure limiting valves. A conduit 103 interconnects the two valves 101 and 102 to form a shunt path for hydraulic fluid under pressure across the internal circuit of the unit 76 between the pump and motor. The valves 101 and 102 are of the type that permit free flow of hydraulic fluid in one direction therethrough and provide pressure limiting flow action when the hydraulic fluid is passed in the opposite direction therethrough and are connected in bucking relation. Therefore, through adjustment with manual actuators 104, the valves can be independently set to regulate the hydraulic resistance of the shunt path at different values for different flow directions to independently control maximum drive force available at the shaft for each direction of rotation of the same.

More particularly, when the rods24 are being driven into a sewer, they are in compression and are relatively free to bend within the confines of the sewer when an obstruction is encountered. If too much force is applied to the rods at this time, they may bend or even break. On the other hand, when the rods are removed from the sewer, they are under tension and are capable of withstanding much greater forces than when being moved into the sewer. Therefore, to achieve most efficient operation, the valves 101 and 102 can be independently set to regulate the maximum amount of force permissible for the direction of travel of the rods which they individually control, it being understood that one of the valves will control the amount of force applied to the rod when being driven into the sewer and the other controlling the amount of force when the rod is removed from the sewer. Normally the valves will be set so that there will be lesser force applied to the rod when the rods are introduced into a sewer than when removed therefrom to thereby constitute a means responsive to the drive control system for regulating rod loading dependent on direction of travel.

The output shaft 100 of the motor 98 mounts a drive sprocket 106 about which a chain 108 is trained. The

chain 108 is also trained about a drive sprocket 110 which is mounted on a shaft 112 (FIGS. 1 and 3) and which forms a portion of the rod driving mechanism 30. The rod drive mechanism further includes the shaft 1 14 (FIG. 3) and both of the shafts 112 and 114 additionally mount respective pair of sprockets 1 16.

Since the peripheral structure associated with each of the shafts 112 and 114 (with the exception of the bending moment. As a result, the framework mounting the shafts 112 and 114 therefore need not be as strong as corresponding frameworks in prior art devices to provide a considerable savings in weight and stability of the vehicle. One of the flanges130 may also serve as the frame member mounting the bearing 88 and the pivot 96 as mentioned previously.

Referring to FIGS. 2 and 3, the base 124 of the chan-. nel includes a cutout 134 at the end adjacent the post 38 and an aperture 136 near the end adjacent the post 132 through which the outer periphery of the sprocket 116 extends in such a way that the upper runs of the presence of the drive sprocket 110 on the shaft 112) is identical, only the structure pertinent to the shaft 114 will be described.

Turning to FIG. 4, the sprockets 116 are seen to be mounted in such a way that a slight spacing exists between the two with the spacing being sufiicientto, accommodate a conventional pusher block 118 which engages the rods 24 at the couplings 26 and drives the rods through engagement with the couplings into or out of a sewer. As is well-known, the pusher blocks 118 are mounted between a pair of chains 120 with the chains being trained about corresponding ones of the sprockets 116 mounted on each of the shafts 112 and 114. Accordingly, when the shaft 112 is driven through the driving connection from the hydraulic motor 98 in a manner mentioned previously, the chains 120 and the pusher blocks 118 will be moved thereby to drive the rods 24 into or out of the sewer.

The shaft 114 ismounted for rotation by a pair of conventional pillow block bearings 122 on either side of the same with the pillow block bearings 122 secured in depending relation fromthe base 124 of a channel by a suitable means such as nuts and bolts 126. The pitch diameter of the sprockets 116 is chosen so that the upper run of the chains 120, which run constitutes the rod driving run, will tangentially leave the sprockets 116 approximately in the plane of the upper surface of the base 124 so that the base 124 provides some support and confinement against downward movement of the chains 120 and the pusher blocks 118. Since the frictional engagement will exist between the just-mentioned elements, preferably a portion of the base 124 is provided with a hardened portion. In the form of the invention shown in FIG. 4, the hardened portion coniprises a wear plate 128. However, it is to be understood that the invention contemplates that the hardened portion could merely constitute a specially treated part of the base 124 itself.

The channel including the base 124 further includes chains are approximatelyin the plane of the uppersurface .of the base 124 as mentioned previously. With reference specifically to FIG.-3, the notch 134 includes a downturned lip 138 while the aperture 136 includes a similar downturned lip to provide for gentle engagement of the pusher blocks 118 and/or chains 120 with the upper surface of the base 124. In the exemplary embodiment employing a separate wear strip 128, the downturned lips 138 and 140 are .formed by the ends of the wear strip 128. l

The post 132 also mounts, in conjunction with the base 124 of the channel, a neck member 142 through which the rods 24 pass to and from the sewer and the storage means 22 as they approach or leave the lefthand end of the chains 120. The opening of the neck 142 is approximately coaxial with the horn member 32 defining the opening 28 as well as the rod engaging portions of the pusher blocks 118 on the upper run of the chains 120.

Finally, in order to insure positive retention of the rods 24 in the pusher blocks 118,- the driving zone 30 is completed by a backup bar 144 which overlies the upper run of the chains 120 as seen in FIG. 4 as well as the pusher blocks 118 carried by the upper run of the chain 120.

As best seen in FIG. 4, the backup bar 144 comprises an upper plate 145 having a'pair of lower plates 146 secured thereto in such a way as to define a notch 148 through which the upper ends of the pusher blocks 118 pass while being carried by the upper run of the chains 120. The backup bar 144 is mounted in the aforesaid relationship by means'of threaded studs 150 secured to the base 124 of the channel, conventional spacer sleeves 152 interposed between the base 124 and the underside of the backup bar 144 and retaining nuts 154. It will therefore be appreciated that in case of a rod jamup within the driving zone 30, easy access may be had to the same simply by removing the retaining nuts 154 and lifting off the backup bar 144 to clear the same in contrast to prior art constructions wherein the lower run of the chains is the driving run and which required substantially complete disassembly of the driving mechanism to achieve access to the rod jam in the driving zone.

Furthermore, the fact that the entire driving mechanism is substantially below the midpoint of the storage means 22 in an apparatus made according to the invention as opposed to the prior art constructions where it is virtually entirely above the midpoint of the storage means, considerably reduces the height of the center of gravity of the entire device thereby improving stability of the vehicle on which it may be mounted while the vehicle is in motion.

separate safety shields required in prior art construc-v tions. For example, in the exemplary embodiment, the

for the driving tionship flexibly interconnected'to each other and adapted tobe propelled through a conduit;

b. a rotatably mounted rod-like element storagedevice for containing the rod-like elements, said storage device having an exit opening through which the rod-like elements may be seriatirn removed therefrom to be propelled through a conduit or returned thereto when removed from a conduit;

c. means adjacent said opening for propelling the rod-like elements received from the storage means through a conduit, said propelling means including at least one chain mounting, at spaced locations, a plurality of pusher means adapted to engage the rod-like elements, said chain being trained about a pair of spaced sprockets mounted for rotation about respective horizontal axes located so that the upper run of the chain is in'approximately the same horizontal plane as said opening, and motor means for driving at least one of the sprockets;

. means mounting said sprockets in spaced relationship including an elongated, inverted channel-like member including a base having a pair of downwardly extending flanges, said base being located just below the upper run of said chain to support the same and said flanges having a sufficient vertical dimension to intersect the axis of rotation of said sprockets; and

e. whereby the driving run of the chain is easily accessible and all forces present in the driving means are substantially within the periphery of the sprocket mounting means.

2. Apparatus according to claim 1 wherein the upper surface of said channel base includes a hardened surface engaging at least one of said chain and said plurality of pusher means.

'3. Apparatus according to claim 1 further including an elongated rod-like element containing member mounted in a position just above the upper surface of the upper run of said chain, easily releasable securing 8 means holding said rod-like element containing member in said position, said member and said securing means being the sole means mounted above the rrun fsa'd h 'n. R? Appgratu s c brding to claim 1 wherein said mounting means further include bearing means secured to and depending from the base of said channel-like member.

5. A conduit cleaning apparatus comprising:

a. a plurality of generally rod-like elements in end-toend relationship flexibly interconnected to each other andadapted to be propelled through a conduit in conjunction with a work performing member for performing work interiorly of the conduit;

b. a rotatably mounted rod-like element storage deviceffor containing the rod-like element, said storage device having anexit opening through which the rod-like elements may be seriatim removed therefrom to be propelled through a conduit or returned thereto when removed from a conduit; c. means adjacent said opening for propelling the rod-like elements received from-"the storage means through a conduit, said propelling means including at least one chain mounting, at spaced locations, a

plurality of pusher means adapted to engage the rod-like elements, and means for driving the chain in two directions, including a reversible motor; and d. control means for the motor including direction control means and means responsive thereto for causing the motor to apply less of a driving force to the chain, andthus to the rod-like elements, when the rod-like elements are being propelled into a conduit than when the rod-like elements are being returned to the storage means.

6. A conduit cleaning apparatus according-to claim 5 wherein said motor is a hydraulic motor and said lastnamed means comprises a pair of independently operable, hydraulic valves, one settable to control force applied to the chain by the motor for one direction of movement thereof and the other settable to control the force applied to the chain in the other direction of movement thereof.

7. Apparatus according to claim 6 wherein said chain is trained about a pair of spaced sprockets with the upper run of said chain being approximately coaxial with said opening and wherein mounting means are provided for said sprockets, said mounting means being located below the upper run of said chain whereby the upper and driving run of said chain is easily accessible.

8. Apparatus according to claim 6 wherein said chain is trained about a pair of spaced sprockets mounted for rotation about parallel axes and further including means mounting said sprockets in spaced relationship including a pair of elongated elements, one on each side of the chain, and extending directly between the axes of rotation of said sprockets so that forces applied to said mounting means from said sprocket are substantially only tensional and compressional forces and not bending moments.

t F i 

1. A conduit cleaning apparatus comprising: a. a plurality of rod-like elements in end-to-end relationship flexibly interconnected to each other and adapted to be propelled through a conduit; b. a rotatably mounted rod-like element storage device for containing the rod-like elements, said storage device having an exit opening through which the rod-like elements may be seriatim removed therefrom to be propelled through a conduit or returned thereto when removed from a conduit; c. means adjacent said opening for propelling the rod-like elements received from the storage means through a conduit, said propelling means including at least one chain mounting, at spaced locations, a plurality of pusher means adapted to engage the rod-like elements, said chain being trained about a pair of spaced sprockets mounted for rotation about respective horizontal axes located so that the upper run of the chain is in approximately the same horizontal plane as said opening, and motor means for driving at least one of the sprockets; d. means mounting said sprockets in spaced relationship including an elongated, inverted channel-like member including a base having a pair of downwardly extending flanges, said base being located just below the upper run of said chain to support the same and said flanges having a sufficient vertical dimension to intersect the axis of rotation of said sprockets; and e. whereby the driving run of the chain is easily accessible and all forces present in the driving means are substantially within the periphery of the sprocket mounting means.
 2. Apparatus accoRding to claim 1 wherein the upper surface of said channel base includes a hardened surface engaging at least one of said chain and said plurality of pusher means.
 3. Apparatus according to claim 1 further including an elongated rod-like element containing member mounted in a position just above the upper surface of the upper run of said chain, easily releasable securing means holding said rod-like element containing member in said position, said member and said securing means being the sole means mounted above the upper run of said chain.
 4. Apparatus according to claim 1 wherein said mounting means further include bearing means secured to and depending from the base of said channel-like member.
 5. A conduit cleaning apparatus comprising: a. a plurality of generally rod-like elements in end-to-end relationship flexibly interconnected to each other and adapted to be propelled through a conduit in conjunction with a work performing member for performing work interiorly of the conduit; b. a rotatably mounted rod-like element storage device for containing the rod-like element, said storage device having an exit opening through which the rod-like elements may be seriatim removed therefrom to be propelled through a conduit or returned thereto when removed from a conduit; c. means adjacent said opening for propelling the rod-like elements received from the storage means through a conduit, said propelling means including at least one chain mounting, at spaced locations, a plurality of pusher means adapted to engage the rod-like elements, and means for driving the chain in two directions, including a reversible motor; and d. control means for the motor including direction control means and means responsive thereto for causing the motor to apply less of a driving force to the chain, and thus to the rod-like elements, when the rod-like elements are being propelled into a conduit than when the rod-like elements are being returned to the storage means.
 6. A conduit cleaning apparatus according to claim 5 wherein said motor is a hydraulic motor and said last-named means comprises a pair of independently operable, hydraulic valves, one settable to control force applied to the chain by the motor for one direction of movement thereof and the other settable to control the force applied to the chain in the other direction of movement thereof.
 7. Apparatus according to claim 6 wherein said chain is trained about a pair of spaced sprockets with the upper run of said chain being approximately coaxial with said opening and wherein mounting means are provided for said sprockets, said mounting means being located below the upper run of said chain whereby the upper and driving run of said chain is easily accessible.
 8. Apparatus according to claim 6 wherein said chain is trained about a pair of spaced sprockets mounted for rotation about parallel axes and further including means mounting said sprockets in spaced relationship including a pair of elongated elements, one on each side of the chain, and extending directly between the axes of rotation of said sprockets so that forces applied to said mounting means from said sprocket are substantially only tensional and compressional forces and not bending moments. 